{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.687","julian_year":2026.687,"time":"2026-09-08T23:59:28.200Z","years_from_j2000":26.687,"frame":"date","applied":"Proper motion, then precession and nutation. The catalogued J2000 position is carried along the great circle the object's own published motion puts it on, at a constant velocity, and the result is referred to the true equator and equinox of this instant. Those are separate things: the motion moves the object, and the rotation turns the grid under it by about fifty arcseconds a year, with nutation adding up to another seventeen.","excluded":"Parallax, the radial-velocity perspective term, aberration and refraction; each is below the accuracy of the catalogued positions themselves. An object with no published proper motion comes back where the catalogue has it rather than at a fabricated zero, and says so with a null pm_ra_mas_yr. A body with no fixed position is not propagated at all — its place comes from an ephemeris, which is what /api/v1/visible answers with."},"slug":"hip-90988-b","name":"HIP 90988 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":306.7008236295619,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":278.3892816,"dec_deg":-50.211692,"epoch_ra_deg":278.911537,"epoch_dec_deg":-50.191485,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HIP 90988","semi_major_axis_km":203453104.152,"periapsis_km":null,"mass_kg":3.989857908664738e+27,"mass_msun":0.00200656,"constellation":"Telescopium","discovered":"2021","featured":false,"url":"https://spacecatalog.org/object/hip-90988-b","radius_km":85466.54000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HIP 90988","host_v_mag":7.75,"eccentricity":0.081,"uncertainties":{"mass_kg":[1.613405909494604e+26,1.4995184336286443e+26],"distance_ly":[1.2566805233426124,1.2667913710518315],"eccentricity":[0.043,0.042],"host_mass_solar":[0.093,0.093],"host_radius_solar":[0.04,0.04],"host_temperature_k":[57,57],"semi_major_axis_km":[4039142.5089,3889544.6381999995],"orbital_period_days":[1.88939,2.11413],"argument_of_periastron_deg":[2.94,3.991]},"host_mass_solar":1.613,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":3.94,"planets_in_system":1,"discovery_facility":"Multiple Observatories","host_spectral_type":"K1 III","host_temperature_k":4883,"orbital_period_days":455.73816,"periastron_epoch_bjd":2454979.213,"equilibrium_temperature_k":400.77,"argument_of_periastron_deg":264.199},"designations":[{"catalog":"Exoplanet","designation":"HIP 90988 b"},{"catalog":"Host star","designation":"HIP 90988"}],"source":{"id":"exoplanet_archive","name":"NASA Exoplanet Archive (Planetary Systems Composite Parameters)","url":"https://exoplanetarchive.ipac.caltech.edu/cgi-bin/TblView/nph-tblView?app=ExoTbls&config=PSCompPars","license":"Public domain (NASA)"},"updated_at":"2026-09-02T19:50:56.720Z","attribution":"Data from SpaceCatalog.org. Individual records carry their source and license in `source`; attribution is required for CC-BY and CC-BY-SA rows."}